Inmates masking their faces seized control of a prison in Venezuela in a protest against alleged mistreatment.
The gang took a guard hostage at the jail in the capital city of Caracas during unrest which saw one prisoner killed.
More than 100 heavily armoured riot police were deployed to quell the disturbance.
Relatives of men being held behind bars at the prison alleged poor conditions inside.
One woman who was the mother of a prisoner told reporters: "Where is the prisons minister? Why isn't he here to check the place?
"The [inmates] are humans who need their liberty or whatever else they need but these problems are not going to end when they collapse from being hit or mistreatment, just like how they're mistreated daily."
The authorities put down the riot after a standoff and inmates were dispersed to different prisons.